Procedure word


Procedure words or prowords are words or phrases limited to radio telephone procedure used to facilitate communication by conveying information in a condensed standard verbal format. Prowords are voice versions of the much older prosigns for Morse code first developed in the 1860s for Morse telegraphy, and their meaning is identical. The NATO communications manual ACP-125 contains the most formal and perhaps earliest modern glossary of procedure words, but its definitions have been adopted by many other organizations, including the United Nations Development Programme, the U.S. Coast Guard, the Rhode Island Department of Emergency Management, Civil Air Patrol, Military Auxiliary Radio System, and others.
Procedure words are one of several structured parts of radio voice procedures, including Brevity codes and Plain language radio checks. The vast majority of the brevity codes from the U.S. military's Multiservice tactical brevity code are inappropriate for any civilian use, owing to their focus on large weapons and other war-related issues. However, a few are used frequently enough in media to be memorable, including ABORT, BOGEY, BANDIT, FEET WET, FEET DRY, NEGATIVE CONTACT, and NO JOY.

Most important procedure words

According to the U.S. Marine Corps training document FMSO 108, "understanding the following PROWORDS and their respective definitions is the key to clear and concise communication procedures."

THIS IS

This transmission is from the station whose designator immediately follows. For clarity, the station called should be named before the station calling. So, "Victor Juliet zero, THIS IS Golf Mike Oscar three..." or for brevity, "Victor Juliet zero, Golf Mike Oscar three, ROGER, OUT". Never "This is GMO3 calling VJ0", "This is ground control to Major Tom" nor any other reversed combination.

OVER

"This is the end of my transmission to you and a response is necessary. Go ahead: transmit."
Contrary to popular belief, "OVER" and "OUT" are never used at the same time, since their meanings are mutually exclusive. With spring-loaded PTT buttons on modern combined transceivers, the same meaning can be communicated with just "OUT", as in "Ops, Alpha, ETA five minutes. OUT."

OUT

"This is the end of my transmission to you and no answer is required or expected."

ROGER

"I have received your last transmission satisfactorily, radio check is LOUD AND CLEAR." "ROGER" may be used to mean "yes" with regard to confirming a command; however, in Air Traffic Control phraseology, it does not signify that a clearance has been given.
The term originates from the practice of telegraphers sending an "R" to stand for "received" after successfully getting a message. This was extended into the spoken radio realm during World War II, with the "R" changed to the phonetic alphabet equivalent word "Roger". The modern NATO phonetic alphabet uses the word "Romeo" for "R" instead of "Roger", and "Romeo" is sometimes used for the same purpose as "Roger", mainly in Australian maritime operations.
For maritime VHF, "copy" does not mean the same as "roger" or "received". It is used when communications between two other stations which includes information for one's own station has been overheard and received satisfactorily.

WILCO

"I understand and Will Comply." Used on receipt of an order. "Roger" and "Wilco" used together are redundant, since "Wilco" includes the acknowledgement element of "Roger".

SAY AGAIN

"I have not understood your message, please SAY AGAIN". Usually used with prowords "ALL AFTER" or "ALL BEFORE". Example: radio working between Solent Coastguard and a motor vessel, call-sign EG 93, where part of the initial transmission is unintelligible
- All stations, all stations, this is Solent Coastguard, Solent Coastguard. Be advised large shipping vessel entering Southampton Water, currently at position OUT
- Solent Coastguard, Solent Coastguard, this is Echo Golf niner three. SAY AGAIN ALL AFTER position. OVER
At this juncture, Solent Coastguard would reply, giving the position of the shipping vessel preceded with the prowords "I SAY AGAIN":
- All stations, all stations, this is Solent Coastguard. I SAY AGAIN, large shipping vessel entering Southampton water, currently at position one decimal two miles from Calshot Spit on bearing one six five degrees. Vessel restricted in ability to deviate from its course. Do not impede. OUT
The word "REPEAT" should not be used in place of "SAY AGAIN", especially in the vicinity of naval or other firing ranges, as "REPEAT" is an artillery proword defined in ACP 125 U.S. Supp-2 with the wholly different meaning of "request for the same volume of fire to be fired again with or without corrections or changes".

ALL AFTER…

Please repeat the message you just sent me beginning after the word or phrase said after this proword.

ALL BEFORE…

Please repeat the message you just sent me ending before the word or phrase said after this proword.

WAIT OVER

I must pause for a few seconds.

WAIT OUT

I must pause for longer than a few seconds. I will call you back.

READ BACK

Please repeat my entire transmission back to me.

I READ BACK

The following is my response to your READ BACK proword.

CORRECTION

I made an error in this transmission. Transmission will continue with the last word correctly sent.

RADIO CHECK

What is my signal strength and readability; how do you hear me?
I request a response indicating the strength and readability of my transmission, according to plain language radio check standards:
5 by 5 is an older term used to assess radio signals, as in 5 out of 5 units for signal strength and for readability. Other terms similar to 5x5 are "LOUD AND CLEAR" or "Lima and Charlie". Example:
Similar example in shorter form:
If the initiating station cannot hear the responding station, then the initiator attempts a radio-check again, or if the responder's signal was not heard, the initiator replies to the responder with "Negative contact, Alpha 12 OUT".
The following readability scale is used: 1 = bad ; 2 = poor ; 3 = fair ; 4 = good ; 5 = excellent.
Example of correct US Army radio check:
For receiver: A-11 and sender: D-12
A-11 This is D-12 RADIO CHECK, OVER
D-12 This is A-11 ROGER, OVER
A-11 this is D-12 ROGER, OUT

Article 32 Radio Regulations distress and rescue prowords

On the radio, distress and rescue usage takes precedence above all other usage, and the radio stations at the scene of the disaster are authorized to commandeer the frequency and prohibit all transmissions that are not involved in assisting them. These procedure words originate in the International Radio Regulations, and are documented in the Combined Communications-Electronics Board ACP 135 Communications instructions Distress and Rescue Procedures.

MAYDAY

Mayday is used internationally as the official SOS/distress call for voice.
I, my vessel or a person aboard my vessel is in grave and imminent danger, send immediate assistance. This call takes priority over all other calls.

The correct format for a MAYDAY call is as follows:
'
MAYDAY, MAYDAY, MAYDAY,
This is

MAYDAY

My position is
I am
I require immediate assistance
I have
Over

VHF instructors, specifically those working for the Royal Yachting Association, often suggest the mnemonic MIPDANIO for learning the message of a mayday signal:
mayday, identify, position, distress, assistance, number of crew, information, o'''ver.
In aviation a different format is used:
MAYDAY, MAYDAY, MAYDAY
Callsign is stated at the end, followed by either "heavy" or "super", though this is not always necessary
Nature of the emergency

For example: "Mayday, Mayday, Mayday, Earth Air 999, we have lost both of our engines due to a bird strike, we are gliding now."
After that pilot can give, or the controller can ask for, additional information, such as, fuel and number of passengers on board.

PAN-PAN

This is the official urgency voice call.
Meaning "I, my vessel or a person aboard my vessel requires assistance but is not in distress." This overrides all but a mayday call, and is used, as an example, for calling for medical assistance or if the station has no means of propulsion. The correct usage is:
PAN-PAN, PAN-PAN, PAN-PAN
All stations, all stations, all stations
THIS IS
My position is
I am
I require
OVER

SÉCURITÉ

Pronounced , this is the official safety voice call.
"I have important meteorological, navigational or safety information to pass on."
This call is normally broadcast on a defined channel and then moved onto another channel to pass the message. Example:

SÉCURITÉ, SÉCURITÉ, SÉCURITÉ
All stations, all stations, all stations.
This is Echo Golf niner three, Echo Golf niner three, Echo Golf niner three.
For urgent navigational warning, listen on channel six-seven.
OUT
SÉCURITÉ, SÉCURITÉ, SÉCURITÉ
All stations, all stations, all stations.
This is Echo Golf niner tree, Echo Golf niner tree, Echo Golf niner tree.
Floating debris sighted off Calshot Spit.
Considered a danger to surface navigation.
OUT

SEELONCE MAYDAY

"Seelonce" is an approximation rendition of the French word silence - silence)
Indicates that your vessel has an emergency and that you are requiring radio silence from all other stations not assisting you.

SEELONCE DISTRESS

Indicates that you are relaying or assisting a station that has placed a MAYDAY call and you are requiring radio silence from all other stations not assisting you or the station in distress.
When the emergency issue is winding down and then has been resolved, these prowords are used to open up the frequency for use by stations not involved in the emergency.

PRU-DONCE

Indicates that complete radio silence is no longer required and restricted use of the frequency may resume, but immediately giving way to all further distress communications.

SEELONCE FEENEE

Indicates that emergency communications have ceased and normal use of the frequency may resume.

ACP 125(F) procedure words

ProwordMeaningProsign/ OPSIG
ACKNOWLEDGE An instruction to the addressee that the message must be acknowledgedZEV or QSL
ADDRESS GROUPThe group that follows is an address group
ALL AFTERThe portion of the message to which I have reference is all that follows……………AA
ALL BEFOREThe portion of the message to which I have reference is all that precedes…………..AB
ANSWER AFTERThe station called is to answer after call sign……..when answering transmissions.ZGO
ASSUME CONTROLYou will assume control of this net until further noticeZKD
AUTHENTICATEThe station called is to reply to the challenge that followsINT ZNB
AUTHENTICATION ISThe transmission authentication of this message is……….
BREAKI hereby indicate the separation of the text from other portions of the messageBT
BROADCAST YOUR NETLink the two nets under your control for automatic rebroadcast
CALL SIGNThe group that follows is a call sign
CLOSE DOWNStations are to close down when indicated. Acknowledgments are requiredZKJ
CORRECTYou are correct, or what you have transmitted is correct.C
CORRECTIONAn error has been made in this transmission. Transmission will continue with the last word correctly transmitted.
An error has been made in this transmission. The correct version is……
That which follows is a corrected version in answer to your request for verification"
EEEEEEEE
C
C
DISREGARD THIS TRANSMISSION – OUTThis transmission is in error, disregard it. IX-----
EXECUTE TO FOLLOWAction on the message or signal that follows is to be carried out upon receipt of the proword EXECUTE. IX
EXEMPTThe station immediately following is exempted from the collective call or from collective addressXMT
FIGURESNumerals or numbers follow.
FLASHPrecedence FLASH.Z
FROMThe originator of this message is indicated by the address designator immediately followingFM
GRIDThe portion following is a grid reference
GROUPSThis message contains the number of groups indicated by the numeral following.GR
GROUP NO COUNTThe groups in this message have not been counted.GRNC
I AM ASSUMING CONTROLI am assuming control of this net until further noticeZKA
I AUTHENTICATEThe group that follows is the reply to your challenge to authenticateZNB
IMMEDIATEPrecedence IMMEDIATEO
IMMEDIATE EXECUTEAction on the message or signal following is to be carried out on receipt of the EXECUTE. IX
INFOThe addressees immediately following are addressed for informationINFO
I READ BACKThe following is my response to your instructions to read backIRB
I SAY AGAINI am repeating transmission or portion indicated.IMI
I SPELLI shall spell the next word phonetically.
I VERIFYThat which follows has been verified at your request and is repeated. C
MESSAGEA message that requires recording is about to follow. ZBO
MORE TO FOLLOWTransmitting station has additional traffic for the receiving station.B
NEGATIVE No. Cancel message sent by the Delayed Executive Method. ZUG
NET NOWAll stations are to net their radios on the unmodulated carrier wave that I am about to transmit.ZRC2
NO PLAYDuring exercises the words NO PLAY are used to distinguish real activity from messages concerned with exercise play e.g. a real emergency or real casualty. The first words of any message is to contain the words exercise NO PLAY
NOTHING HEARDTo be used when no reply is received from a call station.ZGN
NUMBERStation serial number.NR
OUTThis is the end of my transmission to you and no answer is required or expected.AR
OVERThis is the end of my transmission to you and a response is necessary. Go ahead, transmitK
PRIORITYPrecedence PRIORITYP
READ BACKRepeat this entire transmission back to me exactly as receivedG
REBROADCAST YOUR NETLink the two nets under your control for automatic rebroadcast.
RELAY Transmit this message to all addressees. The address component is mandatory when this proword is used.T or ZOF
RELAY THROUGHRelay your message through call sign………ZOK
ROGERThis is a method of receipt. I have received your last transmission satisfactorily.R
ROUTINEPrecedence ROUTINE.R
SAY AGAINRepeat all of your last transmission. Followed by identification data means “Repeat………….”IMI
SEND YOURI am ready to receive your message, report, etc.K
SERVICEThe message that follows is a SERVICE messageSVC
SIGNALSThe groups that follow are taken from a signal book.
SILENCE Cease transmissions on this net immediately. Silence will be maintained until lifted. HM HM HM
SILENCE LIFTEDSilence is lifted. ZUG HM HM HM
SPEAK SLOWERYour transmission is too fast. Reduce speed of transmission.QRS
STOP REBROADCASTINGCut the automatic link between the two nets that are being rebroadcast and revert to normal working.
THIS ISThis transmission is from the station whose designator immediately follows.DE
THIS IS A DIRECTED NETFrom now until further notice this net is directed.ZKB
THIS IS A FREE NETFrom now until further notice this net is free.ZUG ZKB
THROUGH MERelay your message through meZOE
TIMEThat which immediately follows is the time or datetime group of the message.QTR
TOThe addressees immediately following are addressed for actionTO
--TO--The portion of the message to which I have reference is all that which appears between the groups………and………
UNKNOWN STATIONThe identity of the station with whom I am attempting to establish communication is unknown.AA
USE ABBREVIATED CALL SIGNSCall signs are to be abbreviated until further notice.
USE ABBREVIATED PROCEDUREAs conditions are normal, all stations are to use abbreviated procedure until further notice.
USE FULL CALL SIGNSCall signs are to be sent in full until further notice
USE FULL PROCEDUREAs conditions are not normal, all stations are to use full procedure until further notice.
VERIFYVerify entire message with the originator and send correct version. J
WAITI must pause for a few secondsAS
WAIT – OUTI must pause for longer than a few seconds.AS AR
WILCOI have Received your signal, understand it, and will comply.
To be used only by the addressee. Since the meaning of ROGER is included in that of WILCO, the two prowords are never used together.
WORD AFTERThe word of the message to which I have reference is that which follows…………..WA
WORD BEFOREThe word of the message to which I have reference is that which precedes…………..WB
WORDS TWICECommunication is difficult. Transmit each phrase twice. QSZ
WRONGYour last transmission was incorrect. The correct version is…….ZWF

Aviation radio prowords

More formally known as "Aeronautical Mobile communications", radio communications from and to aircraft are governed by rules created by the International Civil Aviation Organization. ICAO defines a very similar but shorter list of prowords in Annex 10 of its Radiotelephony Procedures. Material in the following table is quoted from their list. ICAO also defines "ICAO Radio Telephony Phraseology".
ProwordMeaningNotes
ACKNOWLEDGELet me know that you have received and understood this message
AFFIRMYes.
APPROVEDPermission for proposed action granted.
BREAKI hereby indicate the separation between portions of the message.
BREAK BREAKI hereby indicate the separation between messages transmitted to different aircraft in a very busy environment
CANCELAnnul the previously transmitted clearance
CHECKExamine a system or procedure
CLEAREDAuthorized to proceed under conditions specified.
CONFIRMI request verification of:.
CONTACTEstablish communications with...
CORRECTTrue or Accurate
CORRECTIONAn error has been made in this transmission. The correct version is...
DISREGARDIgnore
HOW DO YOU READWhat is the readability of my transmission
I SAY AGAINI repeat for clarity or emphasis.
MONITORListen out on Often used by terminal controllers when instructing the recipient to tune into a different frequency and listen in, but refrain from creating unnecessary radio traffic.
NEGATIVE"No" or "Permission not granted", or "That is not correct" or "Not capable"
OVERMy transmission is ended, and I expect a response from you.
OUTThis exchange of transmissions is ended and no response is expected.
READ BACKRepeat all, or the specified part, of this message back to me exactly as received.
RECLEAREDA change has been made to your last clearance and this new clearance supersedes your previous clearance or part thereof.
REPORTPass me the following information...
REQUESTI should like to know...
ROGERI have received all of your last transmission.-
SAY AGAINRepeat all, or the following part, of your last transmission.
SPEAK SLOWERReduce your rate of speechNormal rate of speech is to never exceed 100 words per minute. This rate is still too fast for most people to write or type, so SPEAK SLOWER means a significant drop.
STANDBYWait and I will call you.
UNABLEI cannot comply with your request, instruction, or clearance.
WILCOI understand your message and will comply with it.
WORDS TWICE Communication is difficult. Please send every word, or group of words, twice.

Marine radio prowords

Marine radio procedure words follow from the ACP-125 definition, and those in the International Radio Regulations published by the ITU, and should be used by small vessels as their standard radio procedure. Beginning in 2001, large vessels, defined as being 500 gross tonnage or greater, the International Convention on Standards of Training, Certification and Watchkeeping
for Seafarers has required that a restricted and simplified English vocabulary with pre-set phrases, called Standard Marine Communication Phrases, be used and understood by all officers in charge of a navigational watch. These rules are enforced by the International Maritime Organization. The IMO describes the purpose of SMCP, explaining "The IMO SMCP includes phrases which have been developed to cover the most important safety-related fields of verbal shore-to-ship, ship-to-ship and on-board communications. The aim is to get round the problem of language barriers at sea and avoid misunderstandings which can cause accidents."
The SMCP language is not free-form like the standard radio voice procedures and procedure words. Instead, it consists of entire pre-formed phrases carefully designed for each situation, and watch officers must pass a test of their usage in order to be certified under international maritime regulations. For example, ships in their own territorial waters might be allowed to use their native language, but when navigating at sea or communicating with foreign vessels in their own territorial waters, they should switch to SMCP, and will state the switch over the radio before using the procedures. When it is necessary to indicate that the SMCP are to be used, the following message may be sent: "Please use Standard Marine Communication Phrases." "I will use Standard Marine Communication Phrases."

SMCP Procedure words

Clear

"Clear" is sometimes heard in amateur radio transmissions to indicate the sending station is done transmitting and leaving the airways, i.e. turning off the radio, but the Clear proword is reserved for a different purpose, that of specifying the classification of a 16-line format radio message as one which can be sent in the clear, as well as being reserved for use in responding to the Radio Check proword to indicate the readability of the radio transmission.

Affirmative

"Confirm" or "yes" and sometimes shortened to Affirm is heard in several radio services, but is not listed in ACP-125 as a proword because in poor radio conditions it can be confused with Negative. Instead, the proword Correct is used.

Negative

Means "no", and can be abbreviated to Negat. Because over a poor quality connection the words "affirmative" and "negative" can be mistaken for one another, United States Navy instruction omits the use of either as prowords. Sailors are instructed to instead use "yes" and "no".

Examples of radio communication using procedure words

Example 1

Two helicopters, call signs "Swiss 610" and "Swiss 613", are flying in formation :
Anytime a radio call is made, there is some kind of response indicating that the original call was heard. 613's "ROGER" confirms to 610 that the information was heard. In the second radio call from 610, direction was given. 613's "WILCO" means "will comply."
Reading back an instruction confirms that it was heard correctly. For example, if all 613 says is "WILCO", 610 cannot be certain that he correctly heard the heading as 090. If 613 replies with a read back and the word "Wilco" then 610 knows that the heading was correctly understood, and that 613 intends to comply.

Example 2

The following is the example of working between two stations, EG93 and VJ50 demonstrating how to confirm information: